The invention relates to a wheel rim having a tire sensor for a pneumatic tire, and more particularly, to a wheel rim having a tire sensor for a pneumatic tire that has a sensor firmly attached to the wheel rim and the sensor is easy to be changed or performed maintenance.
There are many sensing apparatuses for monitoring tire pressure in the prior art for a pneumatic tire vehicle. For example, a U.S. Pat. No. 4,048,614 xe2x80x9cLow Tire Pressure Warning Devicexe2x80x9d granted to Shumway et al. on Sep. 13, 1977 discloses a tire-pressure warning system that, being installed on the wheel rim, includes a wireless transmitter for actuating a power source, a switch, and a diaphragm. The warning system can trigger the wireless transmitter to provide driver with warning signal when the tire pressure is lower than a predetermined pressure value. But the above-mentioned warning apparatus can only provide warning signal when the vehicle has excessive low tire pressure. Besides, the constituted members of the warning apparatus is rather complicated, thereby, the warning apparatus is not applicable to the modern vehicles.
Another U.S. Pat. No. 5,844,131 xe2x80x9cTire Pressure Sensor Apparatus for a Pneumatic Tire Vehiclexe2x80x9d granted to Gabelmann et al. on Dec. 1, 1998 discloses a tire pressure sensing apparatus. The sensing apparatus includes a housing having at least two base seat members for placing the apparatus on the wheel rim platform and adjustably supporting the housing to be fixed in place by acting together with a wheel valve rod.
Still another U.S. Pat. No. 6,055,855 xe2x80x9cTire Pressure Sensor Wheel Attachment Apparatusxe2x80x9d granted to Straub et al. on May 2, 2000 discloses an apparatus for fixing on the wheel rim of a vehicle. The apparatus possesses a pressure sensor fixing on the wheel rim by threaded connection with a tire valve rod.
In addition, U.S. patent application Ser. No. 09/910,725 filed on Jul. 24, 2001 (corresponding to Taiwan (R.O.C.) Patent application number 089,117,039 entitled xe2x80x9cA Method and an Apparatus for Monitoring Pneumatic Tire Pressurexe2x80x9d) discloses a sensor module, attached to a pneumatic tire, for sensing the tire pressure and transmitting the signals obtained from the tire pressure by wireless frequency. Moreover, U.S. patent application Ser. No. 09/941,567 filed on Aug. 30, 2001 (corresponding to Taiwan (R.O.C.) Patent application number 089,118,096 entitled xe2x80x9cTire Condition Sensor of Pneumatic Tire of a Vehiclexe2x80x9d) discloses a tire pressure sensor attached to a pneumatic tire. These two applications are incorporated herein by reference in their entirety.
The aforementioned prior arts generally make use of a valve rod of the tire to attach the tire-condition sensor on the wheel rim platform. But it goes without saying that the balance of the tire will be affected as the sensor is attached to the side of the valve rod. Moreover, the aforementioned sensors may become loose and then drop while it is operating since the sensor is fixed by threaded member, thereby, the sensor may become malfunction.
To resolve the above-mentioned problems, it becomes necessary to provide a wheel rim having the sensor firmly attached in order that the tire condition can be monitored constantly.
In the light of the above-mentioned disadvantages, an objective of the invention is to provide a wheel rim having a sensor firmly attached thereon, and interacted with a receiver so as to monitor the service condition of the tire.
Another objective of the invention is to provide a wheel rim having a sensor firmly attached thereon, and is apt to be assembled or disassembled.
To attain the above-mentioned objectives, the wheel rim includes a rim portion having a valve rod, a base seat fixing on the rim portion at a location other than the location of the valve rod, and a sensor embedded in and attached to the base seat. The sensor is used for sensing the conditions of the pneumatic tire and transmitting the obtained signals by radio frequency.
In one aspect of the invention, the base seat of the wheel rim of the sensor has two fastening hooks for fastening the sensor. In addition, the base seat has also two flaps for disassembling the sensor.
In other aspect of the invention, the wheel rim has an upper lid portion for acting together with the base seat so as to firmly fix the sensor. Further, the upper lid portion has also a concave portion that can press the sensor downward to further tightening the sensor while the upper lid portion acts together with the base seat, thereby, can firmly fix the sensor in place.
To sum up, since the rim portion of the invention has a sensing apparatus that can transmit the signal obtained from sensing the condition of the tire of a vehicle by radio frequency to the driver. In this way, the driver can be informed of the condition of the tire to avoid any emergency that might occurs. Moreover, since the sensor is firmly attached to the wheel rim at a location opposite to the valve rod, there is no feeling of concern over the dropping of the sensor, and the sensor can also improve the balancing of the tire. Besides, the sensor can be disassembled easily from the wheel rim for changing new one or performing maintenance.
In order to make the foregoing and other objectives, characteristics, and advantages of the invention more significant and easy to be understood, preferred embodiments with accompanied figures will be illustrated as follows: